Evaluation of Corrosion Resistance of Implant-use Ti6Al4V Alloy in Hank Biological Solution in the Presence of Microorganism's Metabolic Product Lactic Acid

Titanium alloys such as Ti6Al4V is the most used alloy used as implant for biomedical purposes. The conditions for a biomaterial to be selected for a particular application in the human body is that this should to conforms to the physical, chemical and biological characteristics, more precisely to be biocompatible, biofunctional and not ultimately sterilizable. Ti6Al4V alloy has mechanical properties suitable for many biomedical applications and has excellent corrosion resistance, which depends on the presence of a stable passive oxide film forming on its surface. Our study aims to evaluate the corrosion resistance of Ti6Al4V as a function in time with addition of 5 g/L and 10 g/L Lactic acid in biological solution Hank after exposure at 0 h (at immersion time), after 48 h (from immersion) and 168 h (from immersion). The evaluation of corrosion resistance of Ti6Al4V in Hank biological solution with addition of two concentration of Lactic acid it was done by electrochemical methods in terms of open circuit potential and polarization resistance (Rp). Lactic acid is used in this study because it is a component present in human blood in small quantities and is necessary for the metabolic processes used directly by the heart muscle, brain and nervous system. The increased lactic acid content in muscle appears as weight-bearing exercises. This is why it is important to know how the presence of lactic acid in larger quantities affects the implants. The study also highlights the importance of using longer testing times and more realistic solutions when testing biomedical materials.